1. Field of the Invention
The present invention generally relates to baseline wander (BLW) correction, and more particularly to a system and method of correcting BLW for a communication receiver.
2. Description of Related Art
Ethernet is a computer networking that is widely used in constructing a local area network. Fast Ethernet or 100BASE-TX, for example, transfers data at a nominal rate of 100 Mbit/sec. At the transmitting side, data is transferred through a transformer before it is transmitted. At the receiving side, data is transferred through another transformer before it is received by a receiver. The transformer, however, functions as a high-pass filter that decays or blocks DC component of a transferred signal, resulting in baseline wander (BLW) effect. Specifically, the baseline of signal waveform at the receiving side is suffered by the baseline wander effect, particularly when a long string of positive or negative packets is transferred.
A variety of techniques have been disclosed to overcome the baseline wander effect. One of them uses an analog-to-digital converter (ADC) to convert a received analog signal into a digital form. A baseline wander correction scheme is then applied to correct the received signal both in analog domain and digital domain at the same time. However, due to latency existed in the ADC, particularly a pipelined ADC, a delay line or circuit is thus required to hold the analog signal, therefore making the entire circuit area bulky and consuming more power.
For the reason that the conventional BLW correction system could not perform BLW correction in a cost-effective manner, a need has arisen to propose a novel BLW correction scheme to reduce its chip area and consumed power.